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From: Sascha Hauer <s.hauer@pengutronix.de>
To: Barebox List <barebox@lists.infradead.org>
Subject: [PATCH v2 26/34] ARM: mmu32: Assume MMU is on
Date: Wed, 17 May 2023 11:03:32 +0200	[thread overview]
Message-ID: <20230517090340.3954615-27-s.hauer@pengutronix.de> (raw)
In-Reply-To: <20230517090340.3954615-1-s.hauer@pengutronix.de>

As we now always enable the MMU during early initialization we can
safely assume that the MMU is already enabled in __mmu_init() and
drop the code path which enables the MMU.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 arch/arm/cpu/mmu_32.c | 47 +++++++++----------------------------------
 1 file changed, 10 insertions(+), 37 deletions(-)

diff --git a/arch/arm/cpu/mmu_32.c b/arch/arm/cpu/mmu_32.c
index bef4a01670..7cd732580e 100644
--- a/arch/arm/cpu/mmu_32.c
+++ b/arch/arm/cpu/mmu_32.c
@@ -24,12 +24,6 @@
 #define PTRS_PER_PTE		(PGDIR_SIZE / PAGE_SIZE)
 #define ARCH_MAP_WRITECOMBINE	((unsigned)-1)
 
-/*
- * We have a 4GiB address space split into 1MiB sections, with each
- * section header taking 4 bytes
- */
-#define ARM_TTB_SIZE	(SZ_4G / SZ_1M * sizeof(u32))
-
 static uint32_t *ttb;
 
 /*
@@ -457,38 +451,19 @@ void __mmu_init(bool mmu_on)
 		pte_flags_uncached = PTE_FLAGS_UNCACHED_V4;
 	}
 
-	if (mmu_on) {
+	/* Clear unpredictable bits [13:0] */
+	ttb = (uint32_t *)(get_ttbr() & ~0x3fff);
+
+	if (!request_sdram_region("ttb", (unsigned long)ttb, SZ_16K))
 		/*
-		 * Early MMU code has already enabled the MMU. We assume a
-		 * flat 1:1 section mapping in this case.
+		 * This can mean that:
+		 * - the early MMU code has put the ttb into a place
+		 *   which we don't have inside our available memory
+		 * - Somebody else has occupied the ttb region which means
+		 *   the ttb will get corrupted.
 		 */
-		/* Clear unpredictable bits [13:0] */
-		ttb = (uint32_t *)(get_ttbr() & ~0x3fff);
-
-		if (!request_sdram_region("ttb", (unsigned long)ttb, SZ_16K))
-			/*
-			 * This can mean that:
-			 * - the early MMU code has put the ttb into a place
-			 *   which we don't have inside our available memory
-			 * - Somebody else has occupied the ttb region which means
-			 *   the ttb will get corrupted.
-			 */
-			pr_crit("Critical Error: Can't request SDRAM region for ttb at %p\n",
+		pr_crit("Critical Error: Can't request SDRAM region for ttb at %p\n",
 					ttb);
-	} else {
-		ttb = xmemalign(ARM_TTB_SIZE, ARM_TTB_SIZE);
-
-		set_ttbr(ttb);
-
-		/* For the XN bit to take effect, we can't be using DOMAIN_MANAGER. */
-		if (cpu_architecture() >= CPU_ARCH_ARMv7)
-			set_domain(DOMAIN_CLIENT);
-		else
-			set_domain(DOMAIN_MANAGER);
-
-		create_flat_mapping(ttb);
-		__mmu_cache_flush();
-	}
 
 	pr_debug("ttb: 0x%p\n", ttb);
 
@@ -499,8 +474,6 @@ void __mmu_init(bool mmu_on)
 				PMD_SECT_DEF_CACHED);
 		__mmu_cache_flush();
 	}
-
-	__mmu_cache_on();
 }
 
 /*
-- 
2.39.2




  parent reply	other threads:[~2023-05-17  9:41 UTC|newest]

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-17  9:03 [PATCH v2 00/34] ARM: MMU rework Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 01/34] ARM: remove unused membase argument Sascha Hauer
2023-05-17 12:45   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 02/34] ARM: remove unused define Sascha Hauer
2023-05-17 12:45   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 03/34] ARM: rename __arm_mem_scratch to arm_mem_scratch Sascha Hauer
2023-05-17 12:46   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 04/34] ARM: put scratch mem area below OP-TEE Sascha Hauer
2023-05-17 12:48   ` Ahmad Fatoum
2023-05-17 13:14     ` Sascha Hauer
2023-05-17 15:50       ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 05/34] ARM: add arm_mem_optee() Sascha Hauer
2023-05-17 12:53   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 06/34] ARM: make arm_mem_scratch() a static inline function Sascha Hauer
2023-05-17 12:53   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 07/34] ARM: define stack base consistently Sascha Hauer
2023-05-17 12:55   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 08/34] ARM: move arm_mem_scratch_get() lower for consistency Sascha Hauer
2023-05-17 12:57   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 09/34] ARM: drop cache function initialization Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 10/34] ARM: Add _32 suffix to aarch32 specific filenames Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 11/34] ARM: cpu.c: remove unused include Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 12/34] ARM: mmu-common.c: use common mmu include Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 13/34] ARM: mmu32: rename mmu.h to mmu_32.h Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 14/34] ARM: mmu: implement MAP_FAULT Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 15/34] ARM: mmu64: Use arch_remap_range where possible Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 16/34] ARM: mmu32: implement zero_page_*() Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 17/34] ARM: i.MX: Drop HAB workaround Sascha Hauer
2023-05-17 13:01   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 18/34] ARM: Move early MMU after malloc initialization Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 19/34] ARM: mmu: move dma_sync_single_for_device to extra file Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 20/34] ARM: mmu: merge mmu-early_xx.c into mmu_xx.c Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 21/34] ARM: mmu: alloc 64k for early page tables Sascha Hauer
2023-05-17 13:03   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 22/34] ARM: mmu32: create alloc_pte() Sascha Hauer
2023-05-17 13:07   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 23/34] ARM: mmu64: " Sascha Hauer
2023-05-17 13:15   ` Ahmad Fatoum
2023-05-17 13:17   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 24/34] ARM: mmu: drop ttb argument Sascha Hauer
2023-05-17 13:23   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 25/34] ARM: mmu: always do MMU initialization early when MMU is enabled Sascha Hauer
2023-05-17 13:29   ` Ahmad Fatoum
2023-05-17  9:03 ` Sascha Hauer [this message]
2023-05-17 13:36   ` [PATCH v2 26/34] ARM: mmu32: Assume MMU is on Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 27/34] ARM: mmu32: Fix pmd_flags_to_pte() for ARMv4/5/6 Sascha Hauer
2023-05-17 13:39   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 28/34] ARM: mmu32: Add pte_flags_to_pmd() Sascha Hauer
2023-05-17 13:43   ` Ahmad Fatoum
2023-05-17 14:44     ` Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 29/34] ARM: mmu32: add get_pte_flags, get_pmd_flags Sascha Hauer
2023-05-17 13:46   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 30/34] ARM: mmu32: move functions into c file Sascha Hauer
2023-05-17 13:48   ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 31/34] ARM: mmu32: read TTB value from register Sascha Hauer
2023-05-17 13:58   ` Ahmad Fatoum
2023-05-17 14:39     ` Sascha Hauer
2023-05-19  6:53       ` Ahmad Fatoum
2023-05-19  7:44         ` Sascha Hauer
2023-05-19  7:52           ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 32/34] ARM: mmu32: Use pages for early MMU setup Sascha Hauer
2023-05-17 14:21   ` Ahmad Fatoum
2023-05-22  8:14     ` Sascha Hauer
2023-05-17  9:03 ` [PATCH v2 33/34] ARM: mmu32: Skip reserved ranges during initialization Sascha Hauer
2023-05-17 14:43   ` Ahmad Fatoum
2023-05-17 14:55     ` Sascha Hauer
2023-05-17 15:56       ` Ahmad Fatoum
2023-05-17  9:03 ` [PATCH v2 34/34] ARM: mmu64: Use two level pagetables in early code Sascha Hauer

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